Aquariums, Ammonia, and McFarlane Dragons

My husband bought three or four McFarlane Dragons before the whole holiday nightmare began, one of which was a water dragon. My son got a ten gallon aquarium for his birthday, and he and his father decided that the water dragon belonged in the tank. A day later, my son informed me that the tank smelled like a giant Sharpie, and he was right. My husband got the tank empty, rinsed the rocks, fake plants, and miniature Coliseum, as well as the charcoal filter and Bio-Wheel. The smell was not there when new water was added. Now, the ammonia in that tank is off the charts, the pH is elevated, and there is an extremely cloudy/filmy look to the water. (No fish in the tank, thankfully!)

We have a 29 gallon tank in the living room, and did not have issues with the water until well after fish were in it, so I'm fairly certain that this is from the dragon. What can we do to make the filter and Bio-Wheel usable? Do we have to replace them? I went to the website for the dragons, but it just says "original paint" for paint type, so I have no idea what they used.

For the record - I told my husband and my son that they shouldn't put the dragon in the water because it wasn't specifically for aquariums. I wasn't present when the package was opened, but they both told me later that it smelled awful. My husband thought it would be OK because he rinsed it first. :shrug: